HEART INVOLVEMENT IN SYSTEMIC-SCLEROSIS - AN ULTRASONIC TISSUE CHARACTERIZATION STUDY

Background-Clinicoepidemiological findings indicate that symptomatic h eart involvement in patients with systemic sclerosis (SSc) predicts a very poor prognosis. At necropsy studies, SSc heart involvement withou t significant coronary lesions is characterised by patchy myocyte necr osis and contraction band necrosis with collagen replacement leading t o myocardial fibrosis. There is a discrepancy between the frequency of clinically evident myocardial disease (25%) and autoptical myocardial fibrosis (81%). Objective-The aim of this study was to detect preclin ical myocardial alterations in SSc patients by ultrasonic videodensito metric analysis. Methods-Thirty five SSc patients (three male, aged 48 .6 (11) SD years, range 22-65) with normal ventricular function and 25 age and sex matched healthy controls were studied. All patients had a negative maximal exercise stress; in all cases arterial hypertension, renal involvement, and diabetes were excluded. Echocardiographic imag es were digitised by a real time videodigitiser (Tomtec Imaging System s). Quantitative texture analysis was performed on data from the septu m and the posterior wall, obtaining mean gray level histogram (MGL) at both end-diastole (d) and end-systole (s). The cyclic variation index (CVI), was calculated according to the formula ((MGLd-MGLs)/MGLd) x 1 00. Left ventricular mass (LVM), body surface corrected, was calculate d according to Penn convention. Results-Comparable systolic and diasto lic blood pressure, LVM, diastolic and systolic function were recorded in both SSc patients and controls. In contrast, in SSc patients the C VI, which is the expression of the intrinsic myocardial structural fun ction, was significantly lower than in controls (septum: -18 (28)% v 3 5 (10)%, p<0.0001; and posterior wall: -13 (32)% v 50 (20)%, p<0.0001) . Changes in cyclic echo amplitude, probably related to myocardial fib rosis, were detected in the large cardial fibrosis, were detected in t he large majority of SSc patients (88%). Conclusions-Ultrasonic videod ensitometric analysis represents a non-invasive, feasible method that can detect early myocardial changes in SSc patients, which could be re lated to both fibrosis and microcirculatory abnormalities. Their poten tial evolution towards ventricular dysfunction and their link with car diac sudden death, because of severe conduction system or rhythm distu rbancies, should be further investigated.